Journal of Cluster Science最新文献

Developing advanced strategies for wastewater treatment is crucial to address the persistent challenge of organic dye pollution. In this study, we report the synthesis of a UiO-66-NH₂/MXene/NaYF₄:Yb, Tm upconversion nanoparticles (UCNPs) ternary composite using a simple sonication stirring approach. The structure and properties of the materials were verified by X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) method, Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Photoluminescence (PL), Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV–Vis DRS) analyses. The composite demonstrated a surface area of ~ 150 m²/g and improved conductivity (0.14–0.25 mS/cm), which facilitated rapid charge transfer and suppressed recombination. Under optimized conditions (20 mg catalyst, neutral pH 7, and 50 mg/L initial dye concentration), the material demonstrated outstanding activity, achieving 98.7% methylene blue removal within 25 min of near-infrared (NIR) irradiation (980 nm). Radical scavenging and Electron Paramagnetic Resonance (EPR) confirmed •OH and •O₂⁻ as the main reactive species. The catalyst maintained > 91% efficiency after five reuse cycles, indicating strong stability. These results highlight the synergistic roles of UiO-66-NH₂, MXene, and UCNPs in enabling an efficient, reusable, and solar relevant photocatalyst for sustainable wastewater purification.

The growing demand for efficient and sustainable energy storage systems has driven the need for innovative electrode materials that provide high capacitance, extended cycle life, and environmental compatibility. Conventional electrode materials frequently exhibit poor energy density and restricted structural stability. This work involved the fabrication of a nitrogen-doped activated carbon/zinc hexacyanoferrate (N-AC/ZnHCF) hybrid electrode utilizing biomass generated from jackfruit peels as a sustainable carbon source. XRD studies validated the crystalline structure of ZnHCF, whilst BET tests indicated a substantial increase in surface area from 50 m² g⁻¹ (ZnHCF) to 95 m² g⁻¹ (N-AC/ZnHCF), hence enhancing ion transport. SEM and TEM investigations demonstrated a uniform distribution of ZnHCF nanoparticles over the porous carbon matrix, while XPS confirmed effective nitrogen doping and the existence of redox-active species. The N-AC/ZnHCF electrode exhibited a high specific capacity of 457 C g-¹ in a three-electrode system and 247 C g-¹ in a two-electrode arrangement. The asymmetric supercapacitor device attained an energy density of 48.5 Wh kg⁻¹ at a power density of 750 W kg⁻¹, demonstrating remarkable cycling stability of 91.6% after 5000 cycles. These findings illustrate the promise of biomass-derived hybrid electrodes as sustainable and high-performance materials for next-generation supercapacitor applications.

The speciation of Ag⁺ in DMSO remains a challenging question due to the formation of equilibrated polynuclear species of unknown nature. This contribution illustrates a possible presence of [Ag₄(µ₂-DMSO)₆(DMSO)₂]⁴⁺ polynuclear moiety as a component of Ag⁺ speciation in DMSO solution. This cation was isolated in the solid state by the assist of [SiW₁₂O₄₀]^4– as a counter anion. The dried crystals of [Ag₄(µ₂-DMSO)₆(DMSO)₂][SiW₁₂O₄₀]·3DMSO·0.7H₂O (1) have been characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), FT-IR and TGA. Argentophilic interactions in the cation were studied by quantum-chemical calculations, revealing non-uniform Ag–O interaction of the “central” DMSO ligand with three closest surrounding Ag atoms. The solutions of 1 in CH₃CN were studied by high performance liquid chromatography coupled with ICP (HPLC-ICP-AES) and electrochemistry. The results indicate that the [Ag₄(µ₂-DMSO)₆(DMSO)₂]⁴⁺ complex undergoes speciation in the solution with the formation of several silver containing species, whose chromatographic indication is possible owing to slow exchange kinetics between DMSO and CH₃CN ligands. Such mixed ligand complexes are quite unusial and need further characterization.

The reactivity of [M₂(CO)₈(NCMe)₂] (M = Mn, Re) with EPh₃ (E = As, Sb) has been illustrated. Bimetallic manganese-arsenic complexes, [Mn₂(CO)₇(µ-AsPh₂)(AsPh₃)(µ-H)] (1) and [Mn₂(CO)₈(µ-AsPh₂)₂] (2) were produced from the reaction of [Mn₂(CO)₈(NCMe)₂] with AsPh₃ in toluene at 110 °C. The controlled experiment shows that 1 is a precursor of 2. It can be speculated that activation of one phenyl group from the coordinated AsPh₃ of 1 formed a second bridging (µ-AsPh₂) ligand. The cleaved phenyl group most probably combines with the departed edge-bridging hydride to produce benzene as a byproduct. In contrast, a similar reaction with SbPh₃ gave [Mn₂(CO)₈(µ-SbPh₂)₂] (3) as the sole product. On the other hand, identical reaction of [Re₂(CO)₈(NCMe)₂] and AsPh₃ resulted a new type of rhenium-arsenic bimetallic complex [Re₂(CO)₅(σ-Ph)(µ-MeCO₂)(µ-AsPh₂)₂] (5) along with two previously reported hydride compounds [Re₂(CO)₆(AsPh₃)₂(µ-AsPh₂)(µ-H)] (4) and [Re(CO)₄(AsPh₃)H] (6). The coordination mechanism of the µ-MeCO₂ ligand is unknown, as its source is unpredictable. However, we believe that the three-electron donor µ-MeCO₂ ligand is formed by hydrolysis of a coordinated MeCN ligand by moisture. Molecular structures of the new products 1, 3, and 5 were unambiguously established through spectroscopic data and single-crystal X-ray diffraction studies. The bonding in these new complexes has been examined by density functional theory (DFT) calculations.

Graphical Abstract

Carbon–arsine and carbon–antimony bonds activation of AsPh₃ and SbPh₃ at dimanganese and dirhenium centers in bimetallic complexes.

The development of innovative biomaterials for effective gastric hemostasis is crucial for improving the management of gastrointestinal bleeding, a condition that poses significant clinical challenges. This study introduces melanin-augmented mangiferin-chitosan nanocomposites (M@Ch-Me NCs) as a multifunctional approach to achieving gastric hemostasis. These NCs combine the unique properties of chitosan, mangiferin, and melanin to address various aspects of gastric bleeding, including inflammation, oxidative stress, and tissue repair. Chitosan, a biocompatible and biodegradable polymer, serves as the structural foundation of the nanocomposite, providing mucoadhesive properties that facilitate targeted delivery and prolonged retention at the bleeding site. Mangiferin, a natural bioactive compound known for its antioxidant and anti-inflammatory properties, is incorporated to reduce oxidative damage and inflammation in the gastric mucosa. Melanin, a biopolymer with excellent free radical scavenging and photothermal conversion capabilities, augments the nanocomposite by enhancing its stability and therapeutic efficacy. The resulting M@Ch-Me NCs demonstrate significant potential for gastric hemostasis through their ability to promote blood clotting, reduce inflammation, and protect against oxidative stress. This multifunctional approach offers a promising strategy for the treatment of gastric bleeding, with potential applications in various clinical settings. Additional study and clinical trials are necessary to completely assess the effectiveness and wellbeing of these nanocomposites in human patients.

Graphical Abstract

Melanin-augmented mangiferin-chitosan nanocomposites exerts protective effects against gastric bleeding and gastric ulcers through multifunction approaches.

A novel ZnO/Bi₂O₂CO₃-Activated carbon (ZnO/Bi₂O₂CO₃/AC) hybrid nanocomposite was synthesized via a one-step hydrothermal method using biochar derived from Manilkara zapota peel, followed by thermal annealing. The materials were thoroughly characterized for their structural, morphological, optical, and photocatalytic properties. The ZnO/Bi₂O₂CO₃/AC ternary nanocomposite exhibited the optical absorption edges is 450 nm which is higher than the pure materials. The band gap energy for ZnO/Bi₂O₂CO₃/AC ternary exhibited 2.23 eV which is reduced from 3.27 eV. Under visible-light irradiation, it achieved degradation efficiencies of 97% for Rhodamine B and 94% for Methyl Orange with the kinetic rate constants were 0.0219 min^− 1 and 0.0203 min^− 1 respectively. In stability experiment small percentage of diminish after five cycles from 97% to 95.1% indicating that the ternary composite demonstrated remarkable constancy and reproducibility during the photocatalytic process. Scavenger studies confirmed the primary active spices is benzoquinone (superoxide anions) in the photocatalytic process. Furthermore, the nanocomposite showed strong antibacterial activity against E. faecalis and S. mutans, demonstrating its potential for environmental and oral healthcare applications.

Graphical Abstract

In this study, the structure and properties of MB₁₂^0/−(M = Li, Na, K, Rb, Cs) clusters were investigated by combining the CALYPSO structure prediction method with DFT calculations. Alkali metal doping caused minimal geometric changes, mainly adding the dopant to the boron framework. When Li is used as the dopant, the cluster exhibits the highest average binding energy and the largest energy gap, signifying its superior physical and chemical stability. Analysis of the electronic structure reveals that B−2p orbitals dominate the molecular orbitals of the clusters, with significant hybridization between s and p orbitals. This hybridization enhances the stability of the clusters by strengthening the σ and π bonds. AdNDP and LOL analyses further confirmed the stabilizing role of s-p hybridization in CsB₁₂^0/− clusters. This study provides a theoretical basis for understanding the effects of alkali metal doping on the structures and properties of boron clusters and offers valuable insights for further experimental research on boron-based nanomaterials.

Graphical Abstract

We report the synthesis of a Mn₃O₄/g-C₃N₄ nanocomposite through a thermal pyrolysis method and its use as a catalyst for the rapid degradation of Methylene Blue (MB) and Crystal violet (CV) dyes. This catalyst has additionally been utilized in the haloperoxidase-like activity. The as-synthesized nanocomposite was characterized using various techniques to analyze its structure, morphology, chemical composition, bandgap, charge separation and so on. The Mn₃O₄/@g-C₃N₄ nanocomposite exhibited excellent photodegradation of MB dye at optimum pH of 12 under the exposure of solar light. The degradation percentage of MB dye was approximately 92% within 15 min. The nanocomposite was also utilized to evaluate its degradation efficiency for crystal violet (CV) dye, achieving around 99% degradation within 60 min. The Pseudo-first order rate constants for the degradation of MB and CV dyes are 0.121 min^− 1 and 0.103 min^− 1 respectively. The Mn₃O₄/g-C₃N₄ nanocomposite is used to study haloperoxidase activity and demonstrated remarkable effectiveness in the enzymatic reaction. The stability assessments indicated the nanocomposite’s potential stability. The scavenging experiment revealed that the superoxide ion radical (O₂.^.−) is the key reactive species, among other scavengers, that enhances the photodegradation process. This work is the first time reported halo peroxidase-like activities of any nanocomposite alongside the photodegradation of pollutant dyes.

The escalating pollution of aquatic ecosystems by pharmaceutical pollutants, notably acetaminophen (ACE), necessitates the advancement of sophisticated and effective remediation technologies. This study presents a direct Z-scheme TiO₂/CdS photocatalyst supported on hierarchical fibrous HY zeolite (TiO₂/CdS/FHY), synthesised via controlled electrolysis in a deep eutectic solvent followed by ultrasonic probe-assisted impregnation. The unique hierarchical fibrous HY-zeolite scaffold, characterized by an inherent meso–macroporous framework (81.5 m²/g) and demonstrated strong Ti–O–Si interfacial bonding, significantly enhanced nanostructure dispersion, facilitated charge separation, and suppressed electron-hole recombination, as evidenced by quenched photoluminescence. Optical characterization via UV–vis DRS revealed a red shift to 590 nm and a narrowed bandgap of 2.24 eV, enabling efficient visible-light harvesting. Under optimal conditions (10 wt% TiO₂ loading, pH 5, 1.5 g/L catalyst dosage, 10 mg/L ACE concentration), TiO₂/CdS/FHY achieved 86.4% ACE-degradation efficiency and retained > 79% activity over five cycles, with FTIR confirming structural stability. Quenching and band-edge analyses identified (e^–/·O₂^–) and (·OH) radicals as the dominant oxidative species, corroborating a direct Z-scheme charge transfer pathway. This research highlights the significant potential of hierarchical fibrous HY zeolite supported TiO₂/CdS nanostructures as an advanced support material for efficient photocatalytic degradation of emerging pharmaceutical contaminants.

The single-In-atom-doped Cu-based clusters exhibits high catalytic activity in CO₂RR, which is selective to CO with a maximum faradic efficiency, such as the InCu₉₉ cluster [Angew. Chem. Int. Ed., 2025, 64(43): e202512970]. However, the structure evolutions and electronic properties of In doped Cu clusters have not yet been fully clarified. Here, the growth patterns and superatomic properties of InCu_n (n = 1–9) clusters are first analyzed using the genetic algorithm combined with the density functional theory (DFT). The structural transitions of them are found to occur at the InCu₄, where the In atom trends to stabilize at the vertex sites with high-coordination numbers. Among them, the octahedral InCu₅ has a higher stability than that of its neighbors on the average binding energy per atom (E_b), the fragmentation energy (E_f) and the second-order differences of energy (Δ₂E) curves, and can maintain the structural integrity at 700 K. The molecular orbitals reveal that the InCu₅ has a 1S²1P⁶ superatomic electronic shell, which is further confirmed by the electron localisation function (ELF), localised orbital locator (LOL) and density of states (DOS) analysis. The electrostatic potential surfaces confirm the presence of significant σ-hole regions at the Cu atomic sites. These σ-holes induce a red-shift in the C-O stretching frequency and an associated bond elongation, which originates from the donation of Cu 3d¹⁰ electrons into the anti-bonding π* orbital of CO.